An aircraft radar system may transmit a radar signal and receive a radar return signal that may be measured and converted to reflectivity values, and stored in a three-dimensional (3-D) weather volumetric buffer relative to the range associated with the radar return signal. The 3-D weather volumetric buffer may be a data structure stored in memory that includes data that describes a distribution of reflectivity within a three-dimensional space. For example, one or more processors of the aircraft radar system may use non-Doppler processing to measure the signal power of radar return signals, estimate reflectivity values based on the signal power measurements, and populate elements of the 3-D weather volumetric buffer with the estimated reflectivity values. However, ground clutter contamination of a desired weather signal occurs when estimating reflectivity values based on the signal power measurements from non-Doppler processing.